/*
 * Copyright (c) 2010, okazoh_tk. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *  - Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *  - Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 *  - Neither the name of the copyright holder nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef ALKES_GAUSSIAN_FILTER_H_INCLUDED_
#define ALKES_GAUSSIAN_FILTER_H_INCLUDED_

#include "alkes/effector/ImageFilter.h"

namespace alkes {

/// \addtogroup effector
//@{

class AL_EXPORT GaussianFilter
    : public ImageFilter
{
public:

    static GaussianFilter* create(ImageBufferFactory* factory, int32_t kernel, float sigma);

    int32_t getKernel() const;
    const int32_t* getFilter() const;
    int32_t getShiftValue() const;

protected:

    GaussianFilter(ImageBufferFactory* factory, int32_t kernel, int32_t shift, int32_t* filter);
    virtual ~GaussianFilter();

    virtual bool onApply(ImageBuffer* src, intrusive_ptr<ImageBuffer>* dst);

    virtual void destroy();

private:
    static int32_t* createFilter(int32_t kernel, float sigma, int32_t& shift);
    static void destroyFilter(void* filter);

    bool applyFilter(ImageBuffer* src, ImageBuffer* dst);

    struct WindowFilter
    {
        int32_t dx, dy;
        int32_t w, h;
        const uint8_t* src;
        int32_t s_pitch;
        uint16_t s_width, s_height;
        uint8_t* dst;
        int32_t d_pitch;
        uint16_t d_width, d_height;
    };
    void applyWindowFilter(WindowFilter& wf);

private:
    int32_t kernel_;
    int32_t shift_;
    int32_t* filter_;
};

//@}

}

#endif
